docs: def std_check_in(cls, dataset, name, allowed_vals):
          """
          Returns 0 if attr not present, 1 if present but not in correct value, 2 if good
          """
          if name not in dataset.ncattrs():
              return 0
  
          ret_val = 1
          if dataset.getncattr(name) in allowed_vals:
              ret_val += 1
  
          return ret_val